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Kurianowicz K, Klatka M, Polak A, Hymos A, Bębnowska D, Podgajna M, Hrynkiewicz R, Sierawska O, Niedźwiedzka-Rystwej P. Impaired Innate Immunity in Pediatric Patients Type 1 Diabetes-Focus on Toll-like Receptors Expression. Int J Mol Sci 2021; 22:12135. [PMID: 34830017 PMCID: PMC8625857 DOI: 10.3390/ijms222212135] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/23/2021] [Accepted: 10/27/2021] [Indexed: 01/07/2023] Open
Abstract
Type 1 diabetes (DM1) is classified as an autoimmune disease. An uncontrolled response of B and T lymphocytes to the body's own tissues develops in the absence of immune tolerance. The main aim of the study was to evaluate the effect of the duration of type 1 diabetes in children on the expression of TLR receptors and the relationship with the parameters of glycemic control in patients. As a result, we showed significant differences in the level of TLR2, TLR4 and TLR9 expression in patients with DM1 in the early stage of the disease and treated chronically compared to the healthy group. Additionally, in this study, we found that the numbers of CD19+ B cells, CD3+ CD4+, CD3+ CD8+ T cells and NK cells are different for newly diagnosed DM1 individuals, patients receiving chronic treatment and for healthy controls, indicating an important role of these cells in killing pancreatic beta cells. Moreover, higher levels of IL-10 in patients with newly diagnosed DM1 have also been found, confirming the reports found in the literature.
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MESH Headings
- Adolescent
- Antigens, CD19/genetics
- Antigens, CD19/immunology
- B-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- Child
- Child, Preschool
- Diabetes Mellitus, Type 1/blood
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/pathology
- Female
- Gene Expression Regulation/genetics
- Humans
- Immunity, Innate/genetics
- Immunity, Innate/immunology
- Interleukin-10/genetics
- Interleukin-10/immunology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Male
- Pediatrics
- Toll-Like Receptor 2/genetics
- Toll-Like Receptor 4/genetics
- Toll-Like Receptor 9/genetics
- Toll-Like Receptors/genetics
- Toll-Like Receptors/immunology
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Affiliation(s)
- Katarzyna Kurianowicz
- Department of Pediatric Endocrinology and Diabetology, Medical University of Lublin, Gębali 1 St., 20-093 Lublin, Poland; (K.K.); (M.K.)
| | - Maria Klatka
- Department of Pediatric Endocrinology and Diabetology, Medical University of Lublin, Gębali 1 St., 20-093 Lublin, Poland; (K.K.); (M.K.)
| | - Agnieszka Polak
- Department of Endocrinology, Medical University of Lublin, Jaczewskiego 8 St., 20-954 Lublin, Poland;
| | - Anna Hymos
- Department of Experimental Immunology, Medical University of Lublin, Chodźki 4a St., 20-093 Lublin, Poland;
| | - Dominika Bębnowska
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland; (D.B.); (R.H.); (O.S.)
| | - Martyna Podgajna
- Department of Clinica Immunology and Immunotherapy, Medical University of Lublin, Chodźki 4a St., 20-093 Lublin, Poland;
| | - Rafał Hrynkiewicz
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland; (D.B.); (R.H.); (O.S.)
| | - Olga Sierawska
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland; (D.B.); (R.H.); (O.S.)
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Ferreira TB, Hygino J, Wing AC, Kasahara TM, Sacramento PM, Camargo S, Rueda F, Alves-Leon SV, Alvarenga R, Vasconcelos CC, Agrawal A, Gupta S, Bento CAM. Different interleukin-17-secreting Toll-like receptor + T-cell subsets are associated with disease activity in multiple sclerosis. Immunology 2017; 154:239-252. [PMID: 29168181 DOI: 10.1111/imm.12872] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/04/2017] [Accepted: 11/14/2017] [Indexed: 12/12/2022] Open
Abstract
Signalling through Toll-like receptors (TLRs) may play a role in the pathogenesis of autoimmune diseases, such as multiple sclerosis (MS). In the present study, the expression of TLR-2, -4 and -9 was significantly higher on CD4+ and CD8+ T-cells from MS patients compared to healthy individuals. Following in-vitro activation, the proportion of interleukin (IL)-17+ and IL-6+ CD4+ and CD8+ T-cells was higher in the patients. In addition, the proportion of IFN-γ-secreting TLR+ CD8+ T-cells was increased in MS patients. Among different IL-17+ T-cell phenotypes, the proportion of IL-17+ TLR+ CD4+ and CD8+ T-cells producing IFN-γ or IL-6 were positively associated with the number of active brain lesions and neurological disabilities. Interestingly, activation of purified CD4+ and CD8+ T-cells with ligands for TLR-2 (Pam3Csk4), TLR-4 [lipopolysaccharide (LPS)] and TLR-9 [oligodeoxynucleotide (ODN)] directly induced cytokine production in MS patients. Among the pathogen-associated molecular patterns (PAMPs), Pam3Csk4 was more potent than other TLR ligands in inducing the production of all proinflammatory cytokines. Furthermore, IL-6, IFN-γ, IL-17 and granulocyte-macrophage colony-stimulating factor (GM-CSF) levels produced by Pam3Csk4-activated CD4+ cells were directly associated with disease activity. A similar correlation was observed with regard to IL-17 levels released by Pam3Csk4-stimulated CD8+ T-cells and clinical parameters. In conclusion, our data suggest that the expansion of different T helper type 17 (Th17) phenotypes expressing TLR-2, -4 and -9 is associated with MS disease activity, and reveals a preferential ability of TLR-2 ligand in directly inducing the production of cytokines related to brains lesions and neurological disabilities.
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Affiliation(s)
- Thais B Ferreira
- Post-graduate Program in Microbiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Joana Hygino
- Department of Microbiology and Parasitology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Cristina Wing
- Post-graduate Program Neurology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Taissa M Kasahara
- Post-graduate Program in Microbiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Priscila M Sacramento
- Post-graduate Program in Microbiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Solange Camargo
- Lagoa Hospital, Barra da Tijuca Unity, Rio de Janeiro, Brazil
| | - Fernanda Rueda
- Clinical of Diagnosis by Image, Barra da Tijuca Unity, Rio de Janeiro, Brazil
| | - Soniza V Alves-Leon
- Post-graduate Program Neurology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Regina Alvarenga
- Post-graduate Program Neurology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | | | - Cleonice A M Bento
- Post-graduate Program in Microbiology, University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.,Department of Microbiology and Parasitology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.,Post-graduate Program Neurology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
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3
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Barros PO, Dias ASO, Kasahara TM, Ornelas AMM, Aguiar RS, Leon SA, Ruiz A, Marignier R, Araújo ACRA, Alvarenga R, Bento CAM. Expansion of IL-6 + Th17-like cells expressing TLRs correlates with microbial translocation and neurological disabilities in NMOSD patients. J Neuroimmunol 2017; 307:82-90. [PMID: 28495144 DOI: 10.1016/j.jneuroim.2017.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/16/2017] [Accepted: 04/04/2017] [Indexed: 12/17/2022]
Abstract
Different microbial antigens, by signaling through toll-like receptors (TLR), may contribute to Th17-mediated autoimmune diseases, such as neuromyelitis optica spectrum disorder (NMOSD). The objective of this study was to determine the proportion of different Th17-like cell subsets that express TLR in NMOSD patients. For this study, the frequency of different Th17 cell subsets expressing TLR subsets in healthy individuals (n=20) and NMOSD patients (n=20) was evaluated by cytometry. The peripheral levels of soluble CD14 (sCD14) and cytokines were determined by ELISA. Our results demonstrated that the proportion of peripheral CD4+ T cells expressing TLR2, 4 and 9 was significantly higher in NMOSD samples than in healthy subjects. In NMOSD, these cells are CD28+PD-1-CD57- and produce elevated levels of IL-17. Among different TLRs+ Th17-like subsets, the proportion of those that co-express IL-17 and IL-6 was significantly higher in NMOSD patients, which was positively correlated with sCD14 levels and EDSS score. By contrast, the percentage of TLRs+Treg17 cells (IL-10+IL-17+) was negatively related to sCD14 and the severity of NMOSD. In conclusion, the expansion of peripheral IL-6-producing TLR+ Th17-like cells in NMOSD patients was associated with both bacterial translocation and disease severity.
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Affiliation(s)
- Priscila O Barros
- Department of Microbiology and Parasitology, Federal University of the State of Rio de Janeiro, Brazil
| | - Aleida S O Dias
- Department of Microbiology and Parasitology, Federal University of the State of Rio de Janeiro, Brazil
| | - Taissa M Kasahara
- Department of Microbiology and Parasitology, Federal University of the State of Rio de Janeiro, Brazil
| | - Alice M M Ornelas
- Departament of Genetics, Federal University of Rio de Janeiro, Brazil
| | - Renato S Aguiar
- Departament of Genetics, Federal University of Rio de Janeiro, Brazil
| | - Soniza A Leon
- Neurology, Federal University of the State of Rio de Janeiro, Brazil
| | - Anne Ruiz
- Service de Neurologie A and Eugène Devic EDMUS Foundation against Multiple Sclerosis, Observatoire Français de la Sclérose en Plaques (OFSEP), Hôpital Neurologique Pierre Wertheimer, Hospices Civils de Lyon, 69677 Bron, France-Université Lyon 1, Université de Lyon, Lyon, France
| | - Romain Marignier
- Service de Neurologie A and Eugène Devic EDMUS Foundation against Multiple Sclerosis, Observatoire Français de la Sclérose en Plaques (OFSEP), Hôpital Neurologique Pierre Wertheimer, Hospices Civils de Lyon, 69677 Bron, France-Université Lyon 1, Université de Lyon, Lyon, France
| | | | - Regina Alvarenga
- Neurology, Federal University of the State of Rio de Janeiro, Brazil
| | - Cleonice A M Bento
- Department of Microbiology and Parasitology, Federal University of the State of Rio de Janeiro, Brazil; Neurology, Federal University of the State of Rio de Janeiro, Brazil.
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4
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Hossain MJ, Tanasescu R, Gran B. Innate immune regulation of autoimmunity in multiple sclerosis: Focus on the role of Toll-like receptor 2. J Neuroimmunol 2016; 304:11-20. [PMID: 28007303 DOI: 10.1016/j.jneuroim.2016.12.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 12/11/2016] [Indexed: 02/06/2023]
Abstract
Innate immunity relies on a set of germline-encoded receptors including Toll-like receptors (TLRs) that enable the host to discriminate between self and non-self. Multiple sclerosis (MS) is an autoimmune inflammatory demyelinating disease of the central nervous system (CNS). Infections are thought to play an important role in disease susceptibility. The role of innate immunity in MS has been recently appreciated. TLR2, a member of the TLR family, forms heterodimers with either TLR1 or TLR6 and detects a wide range of microbial as well as self-derived molecular structures. It may thus be important both in fighting infection and in activating autoimmunity. In this review, we discuss innate regulation of autoimmunity in MS with a focus on the role of TLR2 signaling.
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Affiliation(s)
- Md Jakir Hossain
- Division of Clinical Neuroscience, University of Nottingham, School of Medicine, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom
| | - Radu Tanasescu
- Division of Clinical Neuroscience, University of Nottingham, School of Medicine, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom; Department of Neurology, Neurosurgery and Psychiatry, University of Medicine and Pharmacy Carol Davila, Colentina Hospital, Bucharest, Romania
| | - Bruno Gran
- Division of Clinical Neuroscience, University of Nottingham, School of Medicine, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom; Department of Neurology, Nottingham University Hospitals NHS Trust, Nottingham NG7 2UH, United Kingdom.
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5
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Overall SA, Bourges D, van Driel IR, Gleeson PA. Increased endogenous antigen presentation in the periphery enhances susceptibility to inflammation-induced gastric autoimmunity in mice. Eur J Immunol 2016; 47:155-167. [PMID: 27759162 DOI: 10.1002/eji.201646572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 09/06/2016] [Accepted: 10/17/2016] [Indexed: 11/12/2022]
Abstract
How the immune system maintains peripheral tolerance under inflammatory conditions is poorly understood. Here we assessed the fate of gastritogenic T cells following inflammatory activation in vivo. Self-reactive T cells (A23 T cells) specific for the gastric H+ /K+ ATPase α subunit (HKα) were transferred into immunosufficient recipient mice and immunised at a site distant to the stomach with adjuvant containing the cognate HKα peptide antigen. Activation of A23 T cells by immunisation did not impact on either immune tolerance or protection from gastric autoimmunity in wild-type BALB/c mice. However, increased presentation of endogenously derived HKα epitopes by dendritic cells (DCs) in the gastric lymph node of IE-H+ /K+ β transgenic mice (IEβ) reduces A23 T-cell tolerance to gastric antigens after inflammatory activation, with subsequent development of gastritis. While HKα-specific A23 T cells from immunised wild-type mice were poorly responsive to in vitro antigen specific activation, A23 T cells from immunised IEβ transgenic mice were readily re-activated, indicating loss of T-cell anergy. These findings show that DCs of gastric lymph nodes can maintain tolerance of pathogenic T cells following inflammatory stimulation and that the density of endogenous antigen presented to self-reactive T cells is critical in the balance between tolerance and autoimmunity.
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Affiliation(s)
- Sarah A Overall
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, the University of Melbourne, Melbourne, Australia
| | - Dorothée Bourges
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, the University of Melbourne, Melbourne, Australia
| | - Ian R van Driel
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, the University of Melbourne, Melbourne, Australia
| | - Paul A Gleeson
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, the University of Melbourne, Melbourne, Australia
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6
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Nifedipine inhibits ox-LDL-induced lipid accumulation in human blood-derived macrophages. Biochem Biophys Res Commun 2015; 457:440-4. [DOI: 10.1016/j.bbrc.2015.01.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Accepted: 01/05/2015] [Indexed: 11/20/2022]
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7
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Batista-Duharte A, Portuondo D, Pérez O, Carlos IZ. Systemic immunotoxicity reactions induced by adjuvanted vaccines. Int Immunopharmacol 2014; 20:170-80. [DOI: 10.1016/j.intimp.2014.02.033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/04/2014] [Accepted: 02/21/2014] [Indexed: 02/08/2023]
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8
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Behniafard N, Aghamohammadi A, Abolhassani H, Pourjabbar S, Sabouni F, Rezaei N. Autoimmunity in X-linked agammaglobulinemia: Kawasaki disease and review of the literature. Expert Rev Clin Immunol 2014; 8:155-9. [DOI: 10.1586/eci.11.94] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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9
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Tremblay MM, Bilal MY, Houtman JCD. Prior TLR5 induction in human T cells results in a transient potentiation of subsequent TCR-induced cytokine production. Mol Immunol 2013; 57:161-70. [PMID: 24128895 DOI: 10.1016/j.molimm.2013.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 08/28/2013] [Accepted: 09/03/2013] [Indexed: 11/24/2022]
Abstract
Activation of TLRs by components required for pathogen viability results in increased inflammation and an enhanced immune response to infection. Unlike their effects on other immune cells, TLR activation in the absence of T cell antigen receptor (TCR) induction has little effect on T cell activity. Instead, the simultaneous induction of TLR and TCR results in increased cytokine release compared to TCR treatment alone. Thus, the current model states that TLRs alter T cell function only if activated at the same time as the TCR. In this study, we tested the novel hypothesis that prior TLR induction can also alter TCR-mediated functions. We found that human T cells responded to ligands for TLR2 and TLR5. However, only prior TLR5 induction potentiated subsequent TCR-mediated cytokine production in human T cells. This response required at least 24h of TLR5 induction and lasted for approximately 24-36h after removal of a TLR5 ligand. Interestingly, prior TLR5 induction enhanced TCR-mediated activation of Akt without increasing Lck, LAT or ERK kinase phosphorylation. Together, our studies show that TLR5 induction leads to a transient increase in the sensitivity of T cells to TCR stimulation by selectively enhancing TCR-mediated Akt function, highlighting that timeframe when TLR5 can potentiate TCR-induced downstream functions are significantly longer that previously appreciated.
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Affiliation(s)
- Mikaela M Tremblay
- Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, United States
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10
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Ma AZS, Zhang Q, Song ZY. TNFa alter cholesterol metabolism in human macrophages via PKC-θ-dependent pathway. BMC BIOCHEMISTRY 2013; 14:20. [PMID: 23914732 PMCID: PMC3751201 DOI: 10.1186/1471-2091-14-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 07/27/2013] [Indexed: 12/14/2022]
Abstract
BACKGROUND Studies have shown that inflammation promoted atherosclerotic progression; however, it remains unclear whether inflammation promoted atherosclerotic progression properties by altering cholesterol metabolism in human macrophages. In the present study, we evaluated a potential mechanism of inflammation on atherogenic effects. We evaluated the ability of TNFa to affect Reverse cholesterol transport (RCT) and cholesterol uptake and its mechanism(s) of action in human macrophages. RESULTS We initially determined the potential effects of TNFa on cholesterol efflux in the human macrophages. We also determined alterations in mRNA and protein levels of ABCA1, ABCG1, LXRa, CD-36, SR-A in human macrophages using quantitative real-time polymerase chain reaction (PCR) and Western immunoblot analyses. The cholesterol efflux rate and protein expression of ABCA1, ABCG1, LXRa, CD-36, SR-A were quantified in human macrophages under PKC-θ inhibition using PKC-θ siRNA. Our results showed that TNFa inhibited the rate of cholesterol efflux and down-regulation the expression levels of ABCA1, ABCG1 and LXRa and up-regulation the expression levels of CD-36, SR-A in human macrophages; PKC-θ inhibition by PKC-θ siRNA attenuated the effect of TNFa on ABCA1, ABCG1, LXRa, SR-A, CD-36 expression. CONCLUSIONS Our results suggest TNFa alter cholesterol metabolism in human macrophages through the inhibition of Reverse cholesterol transport and enhancing cholesterol uptake via PKC-θ-dependent pathway, implicating a potential mechanism of inflammation on atherogenic effects.
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Affiliation(s)
- A Zhi Sha Ma
- Department of Cardiology, Southwest Hospital, The Third Military Medical University, Chongqing, China
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11
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NOD1 cooperates with TLR2 to enhance T cell receptor-mediated activation in CD8 T cells. PLoS One 2012; 7:e42170. [PMID: 22848741 PMCID: PMC3407091 DOI: 10.1371/journal.pone.0042170] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 07/03/2012] [Indexed: 12/24/2022] Open
Abstract
Pattern recognition receptors (PRR), like Toll-like receptors (TLR) and NOD-like receptors (NLR), are involved in the detection of microbial infections and tissue damage by cells of the innate immune system. Recently, we and others have demonstrated that TLR2 can additionally function as a costimulatory receptor on CD8 T cells. Here, we establish that the intracytosolic receptor NOD1 is expressed and functional in CD8 T cells. We show that C12-iEDAP, a synthetic ligand for NOD1, has a direct impact on both murine and human CD8 T cells, increasing proliferation and effector functions of cells activated via their T cell receptor (TCR). This effect is dependent on the adaptor molecule RIP2 and is associated with an increased activation of the NF-κB, JNK and p38 signaling pathways. Furthermore, we demonstrate that NOD1 stimulation can cooperate with TLR2 engagement on CD8 T cells to enhance TCR-mediated activation. Altogether our results indicate that NOD1 might function as an alternative costimulatory receptor in CD8 T cells. Our study provides new insights into the function of NLR in T cells and extends to NOD1 the recent concept that PRR stimulation can directly control T cell functions.
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12
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Nicolò C, Di Sante G, Migliara G, Valentini MG, Piermattei A, Delogu G, Ria F. Intracellular bacteria can cause EAE in SJL mice or modify self-specific T cell repertoire. J Neurol Sci 2011; 311:103-6. [PMID: 21917274 DOI: 10.1016/j.jns.2011.08.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 08/18/2011] [Accepted: 08/29/2011] [Indexed: 10/17/2022]
Abstract
Environment and genetic are both relevant in determining development of Multiple Sclerosis. Many epidemiological observations converge on indicating EBV infection and Vitamin D levels as major players among the environmental factors. Bacteria and bacterial products are however potent triggers of immune responses, and recent work from several laboratories indicates that the microbiota plays a prominent role in "priming" or protecting individuals for development of experimental autoimmune diseases. Here we report our recent work dealing with the role of non-pathogenic mycobacteria and their innate receptors in relapsing-remitting experimental autoimmune encephalomyelitis in the SJL mouse and in mobilization of CNS-reactive T cells. We finally discuss how bacteria are likely involved in the pathogenesis of Multiple Sclerosis, expecially with regard to their role in driving the recurring acute episodes of disease.
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Affiliation(s)
- Chiara Nicolò
- Institute of General Pathology, Università Cattolica del S. Cuore, L.go F.Vito, 1, 00168 Roma, Italy
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13
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Darrasse-Jèze G. RAGE against the self. Clin Immunol 2011; 141:1-2. [PMID: 21889912 DOI: 10.1016/j.clim.2011.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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14
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Microglia and Astrocyte Activation by Toll-Like Receptor Ligands: Modulation by PPAR-gamma Agonists. PPAR Res 2011; 2008:453120. [PMID: 18584038 PMCID: PMC2435222 DOI: 10.1155/2008/453120] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Accepted: 05/05/2008] [Indexed: 12/12/2022] Open
Abstract
Microglia and astrocytes express numerous members of the Toll-like receptor (TLR) family that are pivotal for recognizing conserved microbial motifs expressed by a wide array of pathogens. Despite the critical role for TLRs in pathogen recognition, when dysregulated these pathways can also exacerbate CNS tissue destruction. Therefore, a critical balance must be achieved to elicit sufficient immunity to combat CNS infectious insults and downregulate these responses to avoid pathological tissue damage. We performed a comprehensive survey on the efficacy of various PPAR-γ agonists to modulate proinflammatory mediator release from primary microglia and astrocytes in response to numerous TLR ligands relevant to CNS infectious diseases. The results demonstrated differential abilities of select PPAR-γ agonists to modulate glial activation. For example, 15d-PGJ2 and pioglitazone were both effective at reducing IL-12 p40 release by TLR ligand-activated glia, whereas CXCL2 expression was either augmented or inhibited by 15d-PGJ2, effects that were dependent on the TLR ligand examined. Pioglitazone and troglitazone demonstrated opposing actions on microglial CCL2 production that were TLR ligand-dependent. Collectively, this information may be exploited to modulate the host immune response during CNS infections to maximize host immunity while minimizing inappropriate bystander tissue damage that is often characteristic of such diseases.
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15
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Borrello S, Nicolò C, Delogu G, Pandolfi F, Ria F. TLR2: A Crossroads between Infections and Autoimmunity? Int J Immunopathol Pharmacol 2011; 24:549-56. [DOI: 10.1177/039463201102400301] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Environment has both pathogenic and protective roles in the determination of autoimmune disease development, possibly through infectious agents. TLR2 has the capability to recognize the widest range of PAMPs, and it is important for the recognition of mycobacteria and gram-positive bacteria. Here we review recent information showing that TLR2 ligands, its signaling machinery and the effects of its engagement on T cell polarization and differentiation, all play a decisive role in experimental models of autoimmunity. Thus, we propose that engagement of TLR2 is an important crossroads between encounter with bacteria and development of self-reactive diseases.
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Affiliation(s)
- S. Borrello
- Institutes of General Pathology, Università Cattolica del S. Cuore, Rome, Italy
| | - C. Nicolò
- Institutes of General Pathology, Università Cattolica del S. Cuore, Rome, Italy
| | - G. Delogu
- Institutes of Microbiology and Università Cattolica del S. Cuore, Rome, Italy
| | - F. Pandolfi
- Institutes of Internal Medicine, Università Cattolica del S. Cuore, Rome, Italy
| | - F. Ria
- Institutes of General Pathology, Università Cattolica del S. Cuore, Rome, Italy
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16
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Verthelyi D, Wang V. Trace levels of innate immune response modulating impurities (IIRMIs) synergize to break tolerance to therapeutic proteins. PLoS One 2010; 5:e15252. [PMID: 21203556 PMCID: PMC3008684 DOI: 10.1371/journal.pone.0015252] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Accepted: 11/03/2010] [Indexed: 12/31/2022] Open
Abstract
Therapeutic proteins such as monoclonal antibodies, replacement enzymes and toxins have significantly improved the therapeutic options for multiple diseases, including cancer and inflammatory diseases as well as enzyme deficiencies and inborn errors of metabolism. However, immune responses to these products are frequent and can seriously impact their safety and efficacy. Of the many factors that can impact protein immunogenicity, this study focuses on the role of innate immune response modulating impurities (IIRMIs) that could be present despite product purification and whether these impurities can synergize to facilitate an immunogenic response to therapeutic proteins. Using lipopolysaccharide (LPS) and CpG ODN as IIRMIs we showed that trace levels of these impurities synergized to induce IgM, IFNγ, TNFα and IL-6 expression. In vivo, trace levels of these impurities synergized to increase antigen-specific IgG antibodies to ovalbumin. Further, whereas mice treated with human erythropoietin showed a transient increase in hematocrit, those that received human erythropoietin containing low levels of IIRMIs had reduced response to erythropoietin after the 1(st) dose and developed long-lasting anemia following subsequent doses. This suggests that the presence of IIRMIs facilitated a breach in tolerance to the endogenous mouse erythropoietin. Overall, these studies indicate that the risk of enhancing immunogenicity should be considered when establishing acceptance limits of IIRMIs for therapeutic proteins.
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Affiliation(s)
- Daniela Verthelyi
- Division of Therapeutic Proteins, Office of Biotechnology Products, Center for Drug Evaluation and Research, Food and Drug Administration, Bethesda, Maryland, United States of America.
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Haruta I, Yanagisawa N, Kawamura S, Furukawa T, Shimizu K, Kato H, Kobayashi M, Shiratori K, Yagi J. A mouse model of autoimmune pancreatitis with salivary gland involvement triggered by innate immunity via persistent exposure to avirulent bacteria. J Transl Med 2010; 90:1757-69. [PMID: 20733561 DOI: 10.1038/labinvest.2010.153] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The pathogenesis of autoimmune pancreatitis (AIP) remains unknown. Here, we investigated the possible involvement of chronic, persistent exposure to avirulent bacteria in the pathogenesis of AIP. C57BL/6 mice were inoculated with heat-killed Escherichia coli weekly for 8 weeks. At 1 week and up to 12 months after the final inoculation, the mice were killed to obtain samples. At 1 week after the final E. coli inoculation, marked cellular infiltration with fibrosis was observed in the exocrine pancreas. Cellular infiltration in the exocrine pancreas was still observed up to 12 months after the completion of E. coli inoculation. At 10 months after the final inoculation, duct-centric fibrosis became obvious. Inflammation around the ducts in the salivary glands was also observed. Furthermore, sera from heat-killed E. coli-inoculated mice possessed anti-carbonic anhydrase, anti-lactoferrin, and antinuclear antibodies. Exposure to E. coli-triggered AIP-like pancreatitis in C57BL/6 mice. We propose a hypothetical mechanism for AIP pathogenesis. During the initiation phase, silently infiltrating pathogen-associated molecular patterns (PAMP) and/or antigen(s) such as avirulent bacteria might trigger and upregulate the innate immune system. Subsequently, the persistence of such PAMP attacks or stimulation by molecular mimicry upregulates the host immune response to the target antigen. These slowly progressive steps may lead to the establishment of AIP and associated extrapancreatic lesions. Our model might be useful for clarifying the pathogenesis of AIP.
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Affiliation(s)
- Ikuko Haruta
- Department of Microbiology and Immunology, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan.
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Role for toll-like receptor 4 in TNF-alpha secretion by murine macrophages in response to polysaccharide Krestin, a Trametes versicolor mushroom extract. Fitoterapia 2010; 81:914-9. [DOI: 10.1016/j.fitote.2010.06.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 06/02/2010] [Accepted: 06/03/2010] [Indexed: 11/22/2022]
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Long-term bacterial exposure can trigger nonsuppurative destructive cholangitis associated with multifocal epithelial inflammation. J Transl Med 2010; 90:577-88. [PMID: 20142809 DOI: 10.1038/labinvest.2010.40] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Bacterial infection has become a focus of attention in the pathogenesis of primary biliary cirrhosis (PBC). We earlier reported that the bacterial lipoteichoic acid was detected at the sites of inflammation around damaged bile ducts in the livers of PBC, and PBC patients' sera showed high titers against streptococcal histone-like protein. Here, we investigated whether chronic bacterial exposure could trigger PBC-like epithelial cell damage in normal mouse. BALB/c mice were repeatedly inoculated with various bacteria for 8 weeks. At 1 week (Group 1) and 3, 4, or 20 months (long term; Group 2) after the final inoculation, mice were killed to obtain samples. In the livers of the Streptococcus intermedius (S.i.)-inoculated mice in Group 1, cellular infiltration was predominantly observed around the bile ducts over the hepatic parenchyma. In the S.i.-inoculated mice in Group 2, portal but not parenchymal inflammation was observed in the livers, and periductal cellular infiltrates were detected in the salivary glands. Both S.i.-inoculated Groups 1 and 2 BALB/c mice sera had antibodies against HuCCT1 biliary epithelial cells, anti-nuclear antibodies, and anti-gp210 antibodies, but not anti-mitochondrial antibodies. Immunoreactivity to histone-like DNA-binding protein of S.i. (S.i.-HLP) was detectable around the sites of chronic nonsuppurative destructive cholangitis in the portal area in the livers of both S.i.-inoculated Groups 1 and 2 BALB/c mice. Furthermore, anti-S.i.-HLP antibody bound to synthetic gp210 peptide, as well. Bacteria triggered PBC-like cholangitis, multifocal epithelial inflammation, and autoantibody production. Bacteria are likely involved in the pathogenesis of PBC and of associated multifocal epithelial inflammation.
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Guan Y, Ranoa DRE, Jiang S, Mutha SK, Li X, Baudry J, Tapping RI. Human TLRs 10 and 1 share common mechanisms of innate immune sensing but not signaling. THE JOURNAL OF IMMUNOLOGY 2010; 184:5094-103. [PMID: 20348427 DOI: 10.4049/jimmunol.0901888] [Citation(s) in RCA: 176] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
TLRs are central receptors of the innate immune system that drive host inflammation and adaptive immune responses in response to invading microbes. Among human TLRs, TLR10 is the only family member without a defined agonist or function. Phylogenetic analysis reveals that TLR10 is most related to TLR1 and TLR6, both of which mediate immune responses to a variety of microbial and fungal components in cooperation with TLR2. The generation and analysis of chimeric receptors containing the extracellular recognition domain of TLR10 and the intracellular signaling domain of TLR1, revealed that TLR10 senses triacylated lipopeptides and a wide variety of other microbial-derived agonists shared by TLR1, but not TLR6. TLR10 requires TLR2 for innate immune recognition, and these receptors colocalize in the phagosome and physically interact in an agonist-dependent fashion. Computational modeling and mutational analysis of TLR10 showed preservation of the essential TLR2 dimer interface and lipopeptide-binding channel found in TLR1. Coimmunoprecipitation experiments indicate that, similar to TLR2/1, TLR2/10 complexes recruit the proximal adaptor MyD88 to the activated receptor complex. However, TLR10, alone or in cooperation with TLR2, fails to activate typical TLR-induced signaling, including NF-kappaB-, IL-8-, or IFN-beta-driven reporters. We conclude that human TLR10 cooperates with TLR2 in the sensing of microbes and fungi but possesses a signaling function distinct from that of other TLR2 subfamily members.
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Affiliation(s)
- Yue Guan
- Department of Microbiology, University of Illinois, B103 CLSL MC110, 601 South Goodwin Avenue, Urbana, IL 61801, USA
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Lee SM, Joo YD, Seo SK. Expression and Function of TLR2 on CD4 Versus CD8 T Cells. Immune Netw 2009; 9:127-32. [PMID: 20157599 PMCID: PMC2816945 DOI: 10.4110/in.2009.9.4.127] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 08/07/2009] [Accepted: 08/18/2009] [Indexed: 12/01/2022] Open
Abstract
Background Toll-like receptors (TLRs) play a fundamental role in innate immunity through their capacity to recognize pathogen-associated molecular patterns. Also, TLRs that are expressed in T cells are reported to function as co-stimulatory receptors. However, the functional capacity of TLRs on CD4 T and CD8 T cells has not been directly compared. Here we compared CD4 and CD8 T cell responses to TLR2 ligand plus TCR-mediated stimulation. Methods TLR2 expression was analyzed on T cell subsets under naïve and alloantigen-primed conditions. We analyzed the effects of TLR2 co-stimulation on proliferation and survival of T cell subsets in vitro when stimulated with soluble anti-CD3 in the presence or absence of synthetic ligand Pam3CSK4. Results TLR2 expression on CD8 T cells was induced following activation; this expression was much higher than on CD4 T cells. Thus, the molecule was constitutively expressed on Listeria-specific memory CD8 T cells. Based on these expression levels, proliferation and survival were markedly elevated in CD8 T cells in response to the TLR2 co-stimulation by Pam3CSK4 compared with those in CD4 T cells. Conclusion Our data show that TLR2 co-stimulation is more responsible for proliferation and survival of CD8 T cells than for that of CD4 T cells.
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Affiliation(s)
- Sun-Mi Lee
- Department of Microbiology and Immunology, College of Medicine, Inje University, Busan 614-735, Korea
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Kubo T, Uchida Y, Watanabe Y, Abe M, Nakamura A, Ono M, Akira S, Takai T. Augmented TLR9-induced Btk activation in PIR-B-deficient B-1 cells provokes excessive autoantibody production and autoimmunity. ACTA ACUST UNITED AC 2009; 206:1971-82. [PMID: 19687229 PMCID: PMC2737165 DOI: 10.1084/jem.20082392] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Pathogens are sensed by Toll-like receptors (TLRs) expressed in leukocytes in the innate immune system. However, excess stimulation of TLR pathways is supposed to be connected with provocation of autoimmunity. We show that paired immunoglobulin (Ig)-like receptor B (PIR-B), an immunoreceptor tyrosine-based inhibitory motif-harboring receptor for major histocompatibility class I molecules, on relatively primitive B cells, B-1 cells, suppresses TLR9 signaling via Bruton's tyrosine kinase (Btk) dephosphorylation, which leads to attenuated activation of nuclear factor kappaB p65RelA but not p38 or Erk, and blocks the production of natural IgM antibodies, including anti-IgG Fc autoantibodies, particularly rheumatoid factor. The autoantibody production in PIR-B-deficient (Pirb(-/-)) mice was further augmented in combination with the Fas(lpr) mutation, which might be linked to the development of autoimmune glomerulonephritis. These results show the critical link between TLR9-mediated sensing and a simultaneously evoked, PIR-B-mediated inhibitory circuit with a Btk intersection in B-1 cells, and suggest a novel way toward preventing pathogenic natural autoantibody production.
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Affiliation(s)
- Tomohiro Kubo
- Department of Experimental Immunology, Institute of Development, Aging, and Cancer, Tohoku University, Sendai 980-8575, Japan
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Boldizsar F, Tarjanyi O, Nemeth P, Mikecz K, Glant TT. Th1/Th17 polarization and acquisition of an arthritogenic phenotype in arthritis-susceptible BALB/c, but not in MHC-matched, arthritis-resistant DBA/2 mice. Int Immunol 2009; 21:511-22. [PMID: 19254958 PMCID: PMC2675029 DOI: 10.1093/intimm/dxp018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Proteoglycan (PG) aggrecan-induced arthritis (PGIA) is a murine model of rheumatoid arthritis (RA). Although BALB/c and DBA/2 mice share the same MHC (H-2d) haplotype, the BALB/c strain is susceptible to PGIA, while DBA/2 mice are resistant. Therefore, these two inbred mouse strains provide an opportunity to study arthritis susceptibility factors excluding the effects of MHC-associated genetic components. The goal of this study was to monitor changes in the cellular composition and activation state following intra-peritoneal (i.p.) immunization to induce PGIA; additionally, we sought to identify new susceptibility factors by comparing PG-induced immune responses in BALB/c and DBA/2 mice. Upon i.p. PG injection, resident naive B1 cells are replaced by both T cells and conventional B cells in the peritoneum of BALB/c mice. These peritoneal T cells produce IFNγ and IL-17, cytokines shown to be important in RA and corresponding arthritis models. Moreover, peritoneal cells can adoptively transfer PGIA to SCID mice, demonstrating their arthritogenic properties. Our results indicate that repeatedly injected antigen leads to the recruitment and activation of immune cells in the peritoneum; these cells then trigger the effector phase of the disease. The migration and activation of Th1/Th17 cells in the peritoneal cavity in response to PG immunization, which did not occur in the arthritis-resistant DBA/2 strain, may be critical factors of arthritis susceptibility in BALB/c mice.
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Affiliation(s)
- Ferenc Boldizsar
- Section of Molecular Medicine, Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL 60612, USA
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Raschi E, Borghi MO, Grossi C, Broggini V, Pierangeli S, Meroni PL. Toll-like receptors: another player in the pathogenesis of the anti-phospholipid syndrome. Lupus 2009; 17:937-42. [PMID: 18827059 DOI: 10.1177/0961203308095140] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The anti-phospholipid syndrome (APS) is a systemic autoimmune disease characterized by an adaptive immune response against self phospholipid (PL)--binding proteins. Although APS is considered as an autoantibody-mediated disease, there is now evidence that anti-phospholipid antibodies (aPL) are necessary but not sufficient to trigger some of the clinical manifestations of the syndrome. For example, mediators of the innate immunity are recognized to be additional second hits able to induce the thrombotic events in the presence of aPL. Finally, environmental agents - in particular infectious ones - were reported to act as triggers for the production of autoantibodies cross-reacting with PL-binding proteins as well as inflammatory stimuli that potentiate the aPL thrombogenic effect. Altogether, these findings suggest a role for the innate immunity in APS pathogenesis. Toll-like receptors (TLR) are receptors that induce prompt inflammatory responses and mediate functional activation in immune effector cells. There is evidence that aPL, and in particular anti-beta(2) glycoprotein I (beta(2)GPI) antibodies, may activate endothelial cells and monocytes through TLR-4-dependent signalling. Whether or not TLR may behave as surface receptors for beta(2)GPI is still matter of research. Drugs or molecules able to interfere with TLR involvement may represent new therapeutic approaches for APS.
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Affiliation(s)
- E Raschi
- Allergy, Clinical Immunology and Rheumatology Unit, IRCCS Istituto Auxologico Italiano, Department of Internal Medicine, University of Milan, Milan, Italy
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Purcell AW, van Driel IR, Gleeson PA. Impact of glycans on T-cell tolerance to glycosylated self-antigens. Immunol Cell Biol 2008; 86:574-9. [PMID: 18626489 DOI: 10.1038/icb.2008.48] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There is now substantial evidence that antigen post-translational modifications are recognized by T cells, and alterations in epitope modification has been linked to a number of autoimmune diseases. An estimated one third of the MHC ligands contain post-translational modification of epitopes. A common post-translational modification of proteins is glycosylation and it is predicted on theoretical grounds that approximately 1-5% of MHC ligands may bear a glycan. From numerous studies over the past 15 years it is clear that glycans can influence T cell responses either by contribution to the structure of the epitope or by influencing the profile of peptide epitopes presented by APCs. The influence of glycans on antigen processing and T cell recognition has particular relevance to the induction of tolerance to self-antigens. Here we discuss the potential impact of glycans on the profile of self-epitopes presented by APCs and the consequence of changes in glycosylation to generate neo self-epitopes resulting in the loss of tolerance and the development of autoimmune diseases. With the recent developments in profiling T cell epitopes, and with strategies for modulating glycosylation in vivo, it is now feasible to directly examine the global influence of glycans on self-tolerance and autoimmunity.
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Affiliation(s)
- Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria, Australia
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T-cell fate and function: PKC-theta and beyond. Trends Immunol 2008; 29:179-85. [PMID: 18328786 DOI: 10.1016/j.it.2008.01.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Revised: 01/24/2008] [Accepted: 01/24/2008] [Indexed: 11/20/2022]
Abstract
The serine/threonine-specific protein kinase C-theta (PKC-theta) is a core component of the immunological synapse that was shown in vitro to play a central role in the activation of T cells after T cell receptor (TCR) and co-stimulatory molecule engagement. In recent years, a series of in vivo studies have shown that the situation is far more complex; specifically, PKC-theta signaling is differentially required for Th1, Th2, Th17 and CD8+ cytotoxic T-cell responses. These studies highlight the combination of signals that directly regulate T-cell differentiation and effector responses. In this review, we highlight recent in vivo studies investigating PKC-theta function and discuss this in the context of how the integration of extrinsic signals determines T cell fate and function.
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